jk, yes, it does, but it also heats with radiant heat if done correctly. We are installing a rumford fireplace. It is one luxury that we really wanted even though it may cost a little bit in efficiency. Maybe its a decision we will regret, maybe not. Time will tell, I guess.
Timber frame owner builder in NJ
- Thread starter emanaresi
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From what I read an open hearth on a 3000 sq ft home would cause an air exchange of up to 3 times per hour. Might want to make sure HVAC guy knows your doing an open hearth if you plan to use it frequently. I love the look but just could see anything but negatives when we were considering it.
There are ways to deal with it, one option is to provide makeup air near the fireplace. Good zoning on the hvac helps a lot too. The fact is, when you sit by a fire, you feel a lot warmer than the air temp on the thermostat in the same room may indicate. We are also building the entire masonry chimney within the home, so we will recapture a lot of the heat that is normally lost into the masonry and outside air. It is a thing that my wife and I have gone back and forth on a lot, but its something we really wanted and saw that it was a key part of our dream home.
The specification as I understand it is 1 cfm per sq inch of flue area. Our design calls for a 16" x16" flue, thats under 300cfm. Not insignificant, but not the end of the world. I have done a lot of research and was against the idea for a while, but the more I understand the entire proposition, the more I believe a lot of the naysayers get their info from the people trying to sell "efficient" fireplaces...
The specification as I understand it is 1 cfm per sq inch of flue area. Our design calls for a 16" x16" flue, thats under 300cfm. Not insignificant, but not the end of the world. I have done a lot of research and was against the idea for a while, but the more I understand the entire proposition, the more I believe a lot of the naysayers get their info from the people trying to sell "efficient" fireplaces...
dave1949
Super Star Member
Have you looked at other masonry fireplaces? The type with circulating flues passing through lots of masonry can be had with somewhat normal looking fireboxes. They aren't burned continuously though. They get fired once or twice daily then closed up. Those types of heaters are a warm mass that gently radiate heat for hours after burning. I suppose nothing really compares to an open fireplace for ambiance if that is your goal.
With a 16x16 flue, you ought to be able to cook in the thing. Have any plans for cooking cranes? :thumbsup:
With a 16x16 flue, you ought to be able to cook in the thing. Have any plans for cooking cranes? :thumbsup:
BitChin1
Silver Member
Hmm how well does this firebox seal when NOT in use?
Also what zone is your building site located and what is typical wind that will be hitting the house?
In a blower door test if this remains open you will see ~ 153,000CFH (in my house this would equal ~ 2.5ACH for this leakage alone - our 3T heat pump would likely have been a 5T to compensate)
I find at my house (SC KS) we get a lot of wind pressure which causes air leakage though any minor void - if you don't have this issue then the air leakage through the flow won't be that severe of an issue.
Anyway the only point is you are designing a very tight/efficient house otherwise and should attempt to maximize the efficiency related to this design element - that said you are building a HOME - it should match your personality and provide satisfaction in finished product
Some trade-offs are worth it as long as understood
Also what zone is your building site located and what is typical wind that will be hitting the house?
In a blower door test if this remains open you will see ~ 153,000CFH (in my house this would equal ~ 2.5ACH for this leakage alone - our 3T heat pump would likely have been a 5T to compensate)
I find at my house (SC KS) we get a lot of wind pressure which causes air leakage though any minor void - if you don't have this issue then the air leakage through the flow won't be that severe of an issue.
Anyway the only point is you are designing a very tight/efficient house otherwise and should attempt to maximize the efficiency related to this design element - that said you are building a HOME - it should match your personality and provide satisfaction in finished product
Some trade-offs are worth it as long as understood
tkappeler
Platinum Member
42" rumsford!!! Wow, that baby will be able to project some heat into the space. It sounds like you have considered it long and hard. It is your home and you have to live with it. The air exchanges/loss through the chimney not withstanding, I think you will be quite happy with the performance of your building envelope and be quite comfortable.
Keep the pictures coming.
tkappeler
Platinum Member
I wish we could have afforded a geothermal system.
Are you in the pinelands? If so, how has it been in getting permits, etc through the pinelands commission?
We actually are not in a pinelands zone and don't have to worry about pinelands commission, otherwise we may have reconsidered the land purchase. That is not a process I want to deal with.
I think I am planning of installing a tight sealing flue damper in addition to a top damper. As I understand it, the top dampers do an excellent job of sealing a chimney when not in use. we are in climate zone 4. We do have wind here, but I think out in the pines it will be pretty well diffused. We are also only a few miles to the bay and our temps are pretty moderate most of the time due to the stabilizing factors of the bay.
See, I see things a little differently. I see that the fact that we are building a tight, high efficiency structures allows a little room to make the exceptions for the things we thing will make the house enjoyable (big windows, open fireplace, etc) I could just build the house as a cube with no windows and make a tremendously efficient walk in cooler, but thats not where me and my family wants to live. Keeping the thermostat in the living area set a little lower and burning a fire in the fireplace in the evening is something we are very much looking forward to. At first I tried to find a nice zero clearance that could capture the feeling and look we wanted, but it just isn't the same. There is one company that makes a zero clearance "high efficiency" rumford fireplace, when I looked at the price, I decided we would build a masonry rumford.
I think I am planning of installing a tight sealing flue damper in addition to a top damper. As I understand it, the top dampers do an excellent job of sealing a chimney when not in use. we are in climate zone 4. We do have wind here, but I think out in the pines it will be pretty well diffused. We are also only a few miles to the bay and our temps are pretty moderate most of the time due to the stabilizing factors of the bay.
See, I see things a little differently. I see that the fact that we are building a tight, high efficiency structures allows a little room to make the exceptions for the things we thing will make the house enjoyable (big windows, open fireplace, etc) I could just build the house as a cube with no windows and make a tremendously efficient walk in cooler, but thats not where me and my family wants to live. Keeping the thermostat in the living area set a little lower and burning a fire in the fireplace in the evening is something we are very much looking forward to. At first I tried to find a nice zero clearance that could capture the feeling and look we wanted, but it just isn't the same. There is one company that makes a zero clearance "high efficiency" rumford fireplace, when I looked at the price, I decided we would build a masonry rumford.
BitChin1
Silver Member
I wish we could have afforded a geothermal system.
Are you in the pinelands? If so, how has it been in getting permits, etc through the pinelands commission?
How deep is your water source? what type of drilling (sand/clay etc or granite?
In our area (understand this varies significantly) county allows pump and dump system with a number of requirements/constraints..
We needed two wells anyway (water for domestic use and a 2nd well for irrigation) so after tax credits our geo was less cost than a standard air source HP or an air conditioner/gas furnace
Anyone considering a Geo system - talk to several installers and evaluate all options (including foregoing the unit entirely in favor of several small min-splits)
